Patent GB-587015-A (GB)
Title: Improvements in or relating to process for preparing 1,3,5-triazinyl-(6)-aminophenyl-arsenic compounds
IPC: C07F9/80
Filed: 1944-09-28
Abstract: 1 : 3 : 5-Triazine derivatives carrying at one of the triazine ring carbon atoms an aminophenyl group substituted by a radical of the structure -As = X where X stands for sulphur or the group = (SR)2 where R may be an aliphatic radical, a mononuclear or polynuclear isocyclic radical or a mononuclear or polynuclear hetrocyclic radical the ring of which consists of carbon and nitrogen atoms are prepared by reacting with H2S gas or a compound of the formula HSR a triazine compound of corresponding structure in which the arsenic substituent in the aminophenyl group has the structure -As = X1 and comprises arsenic acid (-AsO3H2) radicals, and trivalent arsenic oxide and arsenic halogen radicals.  The compounds of the invention have the formula <FORM:0587015/IV/1> Y1 and Y2 may be halogen, amino, or substituted amino and A and B may be hydrogen, halogen, hydroxy, substituted hydroxy, alkyl, amino, or substituted amino.  If the starting material contains arsenic in the form of an arsonic acid radical there is used four molecules of the HSR- type compound.  The first stage in the reaction consists in the reduction of the pentavalent arsenic to the trivalent form, followed by the substitution of the sulphur containing radical.  The reaction may be carried out either in aqueous solution or in an organic solvent.  The reduction of the pentavalent arsenic to the trivalent form may be carried out as described in Specification 573,933.  In examples: (1) (2 : 4-diamino-triazinyl-6)-[4 - oxy - 3 - aminophenyl - arsonic acid] is first reduced to the corresponding arsinoxide and then reacted with glutathione in aqueous solution.  (2) Cystein is reacted with the arsinoxide used in example (1) in either aqueous or alcoholic solution.  (3) Para-[2 : 4-diamino-1 : 3 : 5-triazinyl-(6)] aminophenyl-arsindichloride is treated with potassium thioglycollate in aqueous solution.  In place of the aminophenyl compound there may be used the corresponding 4-oxy-3-amino compound, and instead of potassium thioglycolate there may be used potassium salt of thio-salicyclic acid.  (4) The starting arsonic acid of example (1) is reacted with four molecules of thioglycollic acid without preliminary reduction.  (5) Para-(2 : 4-diamino-1 : 3 : 5-triazinyl-6)-[aminophenyl arsinoxide) in alcoholic suspension is treated with an alcoholic solution of p-sulphydril benzene sulphonic acid.  The benzene sulphonic acid may be replaced by an equivalent amount of p-sulphydril-phenyl-acetic acid.  (6) p-(2-amino - 4 - dimethylamino - 1 : 3 : 5-triazinyl - 6) - [aminophenylarsonic acid is treated in alcoholic solution with thiopropionic acid. (7) p - (2 - chloro - 4 - amino - 1 : 3 : 5 - triazinyl-6)-[aminophenyl arsonic acid) is treated with a -thiolacetamide.  (8) 2 : 4-diamino-1 : 3 : 5-triazinyl - (6) - [amino - 3 - oxy - 4 - phenyl - arsinoxide is prepared by reduction of the corresponding arsonic acid with SO2 gas, followed by treatment of the product with thiophenol. Thionaphthol may be used instead of of thiophenol.  (9) 2-Chloro-4-dimethylamino phenyl arsonic acid is condensed with melamine and the product treated with thiophenal.  (10) 4-Amino-3-methoxy-phenyl-arsonic acid is condensed with cyanuric chloride, the condensation product reduced with SO2 gas in hydrochloric acid and the arsindichloride so formed reacted with potassium thioglycollate.  (11) 2 : 4-Diamino-triazinyl-(6)-aminophenyl arsinoxide is reacted with 2-mercapto-quinoline in aqueous solution.  The corresponding bromo-compound is obtained on starting with 6-bromo-2-mercapto-quinoline.  Additional alternative quinoline derivatives mentioned include 8-mercapto-quinoline 2-mercapto-quinoline, 2-mercapto-4-methyl quinoline, and 2-mercapto -6-methyl quinoline.  Similar compounds are also obtained starting from 2-mercapto-pyridine and b -phthalimido-ethylmercaptan, and 4-mercapto-2 : 6-dimethyl pyridine.  Compounds containing the -As=S radical may be produced either from corresponding compounds containing the -AsO3H2 radical or from corresponding compounds containing a trivalent arsenic group such as -As=O or -AsCl2 by treatment with H2S gas in an aqueous or an organi-medium. Specification 537,690 also is referred to.